There is no more entertaining British historian than Lucy Worsley. She’s the pixieish presenter with an Anna Wintour bob and a propensity for trying on any and every costume she can find. She’ll delve into the history of murder mysteries, the wives of Henry VIII, and the palaces of the great czars.

Lucy Worsley’s 12 Days of Tudor Christmas, debuting tonight on PBS, is the historian and presenter’s latest journey into the past. As in other specials, Worsley dons historically accurate costumes to get into character, but this one illuminates a side of Christmas that was almost lost forever. That is, the traditional English Christmas.

Everyone knows “The 12 Days of Christmas” as one of the most beloved traditional carols of the holiday season. However, what we may not know is how important those 12 days were to the celebration of Christmas centuries ago. Worsley’s special takes us back further than the time when Prince Albert brought Christmas trees to Victorian England, to the court of King Henry VIII. Here, at Hampton Court, Worsley shows us what’s changed, and what hasn’t, about the way we celebrate Christmas.

Essentially, while the weeks leading up to Christmas and New Year’s Eve are a non-stop marathon for revelry today, they were the opposite in Tudor England. Before Henry VIII formed the Church of England, the nation kept to the Catholic traditions of Advent (which demanded austerity in the weeks leading up to Christmas Day) and Epiphany, the so-called Twelfth Day of Christmas. Those 12 days were full of partying, gaming, singing, dancing, flirting, gambling, and, of course, feasting.

Lucy Worsley’s 12 Days of Tudor Christmas takes us through each day of the feast calendar, explaining the context of each forgotten (or mis-remembered) tradition. It’s fascinating for history nerds, but it’s also really fun. Worsley relishes every moment of it, embracing the holiday spirit with giddy glee.

Lucy Worsley’s 12 Days of Tudor Christmas premieres on PBS tonight at 8PM. It should be available to stream on the PBS app after.